1 second

256 megabytes

standard input

standard output

#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <algorithm>
#include <climits>
#include <cstring>
#include <string>
#include <set>
#include <map>
#include <unordered_map>
#include <queue>
#include <stack>
#include <vector>
#include <list>
#define rep(i,m,n) for(i=m;i<=n;i++)
#define rsp(it,s) for(set<int>::iterator it=s.begin();it!=s.end();it++)
#define mod 1000000007
#define inf 0x3f3f3f3f
#define vi vector<int>
#define pb push_back
#define mp make_pair
#define fi first
#define se second
#define ll long long
#define pi acos(-1.0)
#define pii pair<int,int>
#define Lson L, mid, ls[rt]
#define Rson mid+1, R, rs[rt]
#define sys system("pause")
#define intxt freopen("in.txt","r",stdin)
const int maxn=1e3+10;
using namespace std;
ll gcd(ll p,ll q){return q==0?p:gcd(q,p%q);}
ll qpow(ll p,ll q){ll f=1;while(q){if(q&1)f=f*p;p=p*p;q>>=1;}return f;}
inline ll read()
{ll x=0;int f=1;char ch=getchar();while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();}while(ch>='0'&&ch<='9'){x=x*10+ch-'0';ch=getchar();}return x*f;
}
int n,m,k,t,a[maxn][maxn],b[maxn][maxn];
ll ans;
int main()
{int i,j;scanf("%d%d",&n,&m);rep(i,1,n)rep(j,1,m)scanf("%d",&a[i][j]);rep(i,1,n)rep(j,1,m)b[i][j]=a[i][j];rep(i,1,n){rep(j,1,m){b[i][j]+=b[i][j-1];if(b[i][j]&&!a[i][j])ans++;}}rep(i,1,n)rep(j,1,m)b[i][j]=a[i][j];rep(i,1,n){for(j=m;j>=1;j--){b[i][j]+=b[i][j+1];if(b[i][j]&&!a[i][j])ans++;}}rep(i,1,n)rep(j,1,m)b[i][j]=a[i][j];rep(j,1,m){for(i=n;i>=1;i--){b[i][j]+=b[i+1][j];if(b[i][j]&&!a[i][j])ans++;}}rep(i,1,n)rep(j,1,m)b[i][j]=a[i][j];rep(j,1,m){rep(i,1,n){b[i][j]+=b[i-1][j];if(b[i][j]&&!a[i][j])ans++;}}printf("%lld\n",ans);//system("Pause");return 0;
}